It put up satellite imagery showing how smoke has been gathering over the south of the South Island and that “this plume originates from Australia”.
Niwa said Kiwis shouldn’t be surprised to see continued hazy skies and unusually colourful sunsets over the coming week.
Niwa meteorologist Ben Noll told the Herald last month it was possible that hot northwesterly flows predicted to arrive regularly from Australia over summer would make a drift of smoke possible.
“To see it [smoke] in our skies, what you need is a fast start to the fire season across the Tasman, as well as a circulation pattern that favours the west-to-east transport of air from Australia to New Zealand.”
The drifting smoke is raising questions about a possible repeat of the apocalypse-like scenes of 2019-20, with Noll saying other elements would need to align before that happened.
“Whether that’s a southerly change moving up the South Island that drags some dust right out ahead and brings it down to a lower level of the atmosphere, or something else – these are things that just aren’t foreseeable at this point.”
Christchurch, meanwhile, is set to hit a high of 27C today, while Hamner Springs is expected to climb to 28C.
Queenstown is expecting occasional rain and a maximum of 24C, while Dunedin is looking at 23C and Invercargill a top of just 18C.
In the North Island, the East Coast is set for brilliant sunshine with Gisborne reaching 29C and Napier a top of 28C.
Hamilton is also set for radiant weather with a top of 27C, while Rotorua heads for 26C and Taupo 25C.
Further north, Auckland is heading for 26C and a fine afternoon, while Whangārei is set for 24C.
Additional reporting AAP